Magnetic head suspension having a supporting part with an edge formed into a concave shape

ABSTRACT

In a magnetic head suspension according to the present invention, each of paired right and left connecting beams that are positioned on both sides of an open section, with which paired piezoelectric elements are at least partially overlapped in a plan view, in a suspension width direction and connect a proximal end section that is directly or indirectly connected to a main actuator and a distal end section to which the load bending part is connected includes proximal-side and distal-side beams. The distal-side beam is inclined with respect to the proximal-side beam in a plan view such that a connection point between the proximal-side and distal-side beams is located closer to a suspension longitudinal center line relative to a virtual line connecting the proximal end of the proximal-side beam and the distal end of the distal-side beam.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation application of U.S. patentapplication Ser. No. 12/732,692, filed Mar. 26, 2010, the disclosure ofwhich is incorporated herein in its entirety be reference thereto.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a magnetic head suspension forsupporting a magnetic head slider that reads and/or writes data from andto a recording medium such as a hard disk drive.

2. Related Art

Increase in capacity of a magnetic disk device requires improvement inaccuracy for positioning a magnetic head slider on a target track. Inthis regard, there has been proposed a magnetic head suspension thatenables coarse motion of a magnetic head slider in a seek direction by amain actuator such as a voice coil motor as well as micro motion of themagnetic head slider in the seek direction by a piezoelectric elementfunctioning as a sub actuator (for example, see Japanese UnexaminedPatent Application Publications No. H02-227886, No. H11-016311, and No.2001-307442).

The magnetic head suspension including the piezoelectric element asdescribed above needs to be provided with a less rigid region in asupporting part that is swung directly or indirectly by the mainactuator such as a voice coil motor in order to realize the micro motionof the magnetic head slider by the piezoelectric element.

More specifically, the magnetic head suspension provided with thepiezoelectric element includes a load bending part that generates a loadfor pressing the magnetic head slider toward a disk surface, a load beampart that transmits the load to the magnetic head slider, the supportingpart that supports the load beam part via the load bending part and isswung about a swing center directly or indirectly by the main actuator,a flexure part that is supported by the load beam part and thesupporting part while supporting the magnetic head slider, and thepiezoelectric element that is attached to the supporting part.

The supporting part is provided with a proximal end region that isconnected directly or indirectly to the main actuator, a distal endregion to which the load bending part is connected, and the less rigidregion that connects the proximal end region and the distal end regionwith each other. The micro motion of the magnetic head slider isrealized by elastic deformation of the less rigid region in response toexpansion and contraction motion of the piezoelectric element.

In a case where the rigidity is reduced in the less rigid region, themagnetic head slider can be more easily displaced in the seek direction(in a radial direction in parallel with the disk surface) by thepiezoelectric element. On the other hand, such reduction in rigidity ofthe less rigid region increases a stress applied to the piezoelectricelement upon reception of an impact force by a magnetic disk device thatis provided with the magnetic head suspension, and also lowers aresonance frequency of the magnetic head suspension.

SUMMARY OF THE INVENTION

The present invention has been achieved in view of the aboveconventional art, and it is a first object thereof to provide a magnetichead suspension that enables coarse motion of a magnetic head slider bya main actuator as well as micro motion of the magnetic head slider bypiezoelectric elements, the magnetic head suspension capable of reducinga stress applied to the piezoelectric elements upon reception of animpact force while raising a resonance frequency thereof.

In order to achieve the first object, the present invention provides amagnetic head suspension including a load bending part that generates aload for pressing a magnetic head slider toward a disk surface, a loadbeam part that transmits the load to the magnetic head slider, asupporting part that supports the load beam part via the load bendingpart and is swung about a swing center directly or indirectly by a mainactuator, a flexure part that is supported by the load beam part and thesupporting part while supporting the magnetic head slider, and pairedright and left piezoelectric elements that are attached to thesupporting part so as to be symmetrical with each other with respect toa suspension longitudinal center line and have expansion and contractiondirections different from each other, in order to enable micro motion ofthe magnetic head slider in a seek direction, wherein the supportingpart includes a proximal end section that is directly or indirectlyconnected to the main actuator, a distal end section to which the loadbending part is connected, an open section that is positioned betweenthe proximal end section and the distal end section in a suspensionlongitudinal direction, and paired right and left connecting beams thatare positioned on both sides of the open section in a suspension widthdirection and connect the proximal end section and the distal endsection, wherein each of the paired piezoelectric elements has proximaland distal ends that are connected to the proximal end section and thedistal end section, respectively, while being at least partiallyoverlapped with the open section in a plan view as viewed along adirection perpendicular to the disk surface, wherein each of the pairedconnecting beams includes a proximal-side beam that linearly extendsfrom a proximal end connected to the proximal end section to a distalend, and a distal-side beam that linearly extends from a proximal endconnected to the proximal-side beam to a distal end connected to thedistal end section, and wherein the distal-side beam is inclined withrespect to the proximal-side beam in a plan view such that a connectionpoint between the proximal-side beam and the distal-side beam is locatedcloser to the suspension longitudinal center line relative to a virtualline connecting the proximal end of the proximal-side beam and thedistal end of the distal-side beam.

In the magnetic head suspension according to the present invention, eachof the paired piezoelectric elements is mounted to the supporting partso as to have the proximal and distal ends that are connected to theproximal end section and the distal end section of the supporting part,respectively, while being at least partially overlapped with the opensection in a plan view, each of the paired connecting beams provided inthe supporting part so as to be positioned outside the open section inthe suspension width direction and connect the proximal end section andthe distal end section includes the proximal-side beam and distal-sidebeam, and the distal-side beam is inclined with respect to theproximal-side beam in a plan view such that the connection point betweenthe proximal-side beam and the distal-side beam is located closer to thesuspension longitudinal center line relative to a virtual lineconnecting the proximal end of the proximal-side beam and the distal endof the distal-side beam. Accordingly, the magnetic head suspension makesit possible to reduce the stress applied to the piezoelectric elementsupon reception of an impact force and, at the same time, raise theresonance frequency of the magnetic head suspension while excellentlymaintaining easiness of displacement (hereinafter, referred to as micromotion characteristic) of the magnetic head slider in the seek directionby the paired piezoelectric elements.

Preferably, the proximal-side beam is inclined so as to be broughtcloser to the suspension longitudinal center line as extending from theproximal end to the distal end.

Preferably, the distal-side beam has a width that is gradually increasedas extending from the proximal end to the distal end.

In one embodiment, the distal and proximal ends of each of the pairedpiezoelectric elements are fixed to the distal end section and theproximal end section, respectively, in a state where the piezoelectricelement is disposed in the open section such that an end surface on thedistal end side and an end surface on the proximal end side of thepiezoelectric element are opposed at least partially to a proximal endsurface of the distal end section and a distal end surface of theproximal end section, respectively.

In the magnetic head suspension according to the one embodiment, theremay be further provided a distal-end-side support plate, which isconnected to a lower surface of the supporting part that faces the disksurface and on which lower surfaces, on the distal sides, of the pairedpiezoelectric elements that face the disk surface are mounted.

The distal-end-side support plate is connected to the lower surface ofthe supporting part so as to form a gap between a distal edge of thedistal-end-side support plate and a proximal edge of the distal endsection in a plan view as viewed along a direction perpendicular to thedisk surface.

Preferably, the load beam part, the load bending part and thedistal-end-side support plate are integrally formed by a single member.

The magnetic head suspension according to the one embodiment may includea proximal-end-side support plate, which is connected to a lower surfaceof the supporting part that faces the disk surface and on which lowersurfaces, on the proximal sides, of the paired piezoelectric elementsthat face the disk surface are mounted, in addition to/in place of thedistal-end-side support plate.

The proximal-end-side support plate is connected to the lower surface ofthe supporting part so as to form a gap between a proximal edge of theproximal-end-side support plate and a distal edge of the proximal endsection in a plan view as viewed along a direction perpendicular to thedisk surface.

In the magnetic head suspension with the proximal-end-side supportplate, the supporting part may preferably include first and secondplate-like members that are overlapped with and fixed to each other.

The first plate-like member may integrally include a regioncorresponding to the proximal end section, a region corresponding to thepaired connecting beams, and a region corresponding to the distal endsection.

The second plate-like member may integrally include a regioncorresponding to the proximal end section, and a region corresponding tothe proximal-end-side support plate.

In the various configurations included in the magnetic head suspensionaccording to the one embodiment, an inner surface of each of thedistal-side beams that is directed inward in the suspension widthdirection may be preferably formed to be brought closest to an outersurface of the corresponding piezoelectric element that is directedoutward in the suspension width direction at a position of thepiezoelectric element that is away by a predetermined distance from itsdistal end toward its proximal end.

In another one embodiment, the distal and proximal ends of each of thepaired piezoelectric elements are mounted on upper surfaces of distalend section and the proximal end section, respectively, in a state wherethe piezoelectric elements cross over the open section in the suspensionlongitudinal direction.

In any one of the various configurations, a suspension width centralportion of a proximal edge of the distal end section is preferablyformed into a concave shape in a plan view so as to be located on themost distal end in the suspension longitudinal direction at its centerthat is crossed with the suspension longitudinal center line as well asto be brought closer to the proximal end in the suspension longitudinaldirection as extending outward both in the suspension width directionfrom the center.

In any one of the various configurations, a suspension width centralportion of a distal edge of the proximal end section is formed into aconcave shape in a plan view so as to be located on the most proximalend in the suspension longitudinal direction at its center that iscrossed with the suspension longitudinal center line as well as to bebrought closer to the distal end in the suspension longitudinaldirection as extending outward both in the suspension width directionfrom the center.

In any one of the various configurations, the supporting part is a baseplate including a boss portion to which a distal end of a carriage armis joined by a swage processing, the carriage arm being connected to themain actuator. Alternatively, the supporting part is an arm that isconnected to the main actuator.

The present invention has been achieved in view of the aboveconventional art, and it is a second object thereof to provide amagnetic head suspension that enables coarse motion of a magnetic headslider by a main actuator as well as micro motion of the magnetic headslider by piezoelectric elements, the magnetic head suspension capableof reducing a stress applied to the piezoelectric elements uponreception of an impact force and raising a resonance frequency thereofwhile improving micro motion characteristic in the seek direction by thepiezoelectric elements.

In order to achieve the second object, the present invention provides amagnetic head suspension including a load bending part that generates aload for pressing a magnetic head slider toward a disk surface, a loadbeam part that transmits the load to the magnetic head slider, asupporting part that supports the load beam part via the load bendingpart and is swung about a swing center directly or indirectly by a mainactuator, a flexure part that is supported by the load beam part and thesupporting part while supporting the magnetic head slider, and pairedright and left piezoelectric elements that are attached to thesupporting part so as to be symmetrical with each other with respect toa suspension longitudinal center line and have expansion and contractiondirections different from each other, in order to enable micro motion ofthe magnetic head slider in a seek direction, wherein the supportingpart includes a proximal end section that is directly or indirectlyconnected to the main actuator, a distal end section to which the loadbending part is connected, an open section that is positioned betweenthe proximal end section and the distal end section in a suspensionlongitudinal direction, and paired right and left connecting beams thatare positioned on both sides of the open section in a suspension widthdirection and connect the proximal end section and the distal endsection, wherein each of the paired piezoelectric elements has proximaland distal ends that are connected to the proximal end section and thedistal end section, respectively, while being at least partiallyoverlapped with the open section in a plan view as viewed along adirection perpendicular to the disk surface, wherein the distal endsection has a length in the suspension width direction shorter than thatof a distal end of the proximal end section, so that a virtual lineconnecting a center point of a proximal end, which is connected to theproximal end section, of each of the connecting beams and a center pointof a distal end, which is connected to the distal end section, of theconnecting beam is brought closer to the suspension longitudinal centerline as it extends toward the distal end in the suspension longitudinaldirection, wherein each of the paired connecting beams includes aproximal-side beam that extends from the proximal end connected to theproximal end section toward the distal side in the suspensionlongitudinal direction, a distal-side beam that extends from the distalend connected to the distal end section toward the proximal side in thesuspension longitudinal direction, and an intermediate beam connecting adistal end of the proximal-side beam and a proximal end of thedistal-side beam, and wherein each of the connecting beams is bent at aconnection point between the proximal-side beam and the intermediatebeam as well as at a connection point between the distal-side beam andthe intermediate beam, so that an intermediate beam longitudinal lineconnecting center points of proximal and distal ends of the intermediatebeam is across the virtual line.

In the magnetic head suspension according to the present invention, thedistal end section of the supporting part has a length in the suspensionwidth direction shorter than that of a distal end of the proximal endsection so that a virtual line connecting a center point of a proximalend, which is connected to the proximal end section, of each of theconnecting beams and a center point of a distal end, which is connectedto the distal end section, of the connecting beam is brought closer tothe suspension longitudinal center line as it extends toward the distalend in the suspension longitudinal direction. Accordingly, it ispossible to reduce the moment of inertia of the sub actuator around therotational center, thereby raising the resonance frequency in the mainresonance mode. Further, the configuration makes it possible to reducethe weight of the distal side of the supporting part, thereby raisingthe resonance frequency in the bending mode in the z directionperpendicular to the disk surface. As a result, reduced is the stressapplied to the piezoelectric elements upon reception of an impact force,thereby improving the impact resistance of the magnetic head suspension.

Furthermore, in magnetic head suspension according to the presentinvention, each of the connecting beams is bent at a connection pointbetween the proximal-side beam and the intermediate beam as well as at aconnection point between the distal-side beam and the intermediate beam,so that an intermediate beam longitudinal line connecting center pointsof proximal and distal ends of the intermediate beam is across thevirtual line. Accordingly, it is possible to set the bend angles of thebent portions of each of the connecting beams within a desired rangethat allows the elastic deformation of the connecting beam, withoutsignificantly extending the connecting beam outward in the suspensionwidth direction. Therefore, prevented as much as possible isdeterioration in rigidity in the z direction perpendicular to the disksurface, and improved is the micro motion characteristic of the magnetichead slider by the piezoelectric elements (namely, the degree ofeasiness for displacement of the magnetic head slider by thepiezoelectric elements in the seek direction in parallel with the disksurface).

Preferably, the connection point between the proximal-side beam and theintermediate beam is located outside the virtual line in the suspensionwidth direction, and the connection point between the distal-side beamand the intermediate beam is located inside the virtual line in thesuspension width direction.

In one embodiment, the paired piezoelectric elements are disposed so asto expand and contract along the suspension longitudinal line, adistal-side beam longitudinal line that connects center points of theproximal and distal ends of the distal-side beam is farther away fromthe suspension longitudinal center line as it extends toward the distalside in the suspension longitudinal direction, and a proximal-side beamlongitudinal line that connects center points of the proximal and distalends of the proximal-side beam is brought closer to the suspensionlongitudinal center line as it extends in the distal side in thesuspension longitudinal direction.

In another one embodiment, the paired piezoelectric elements aredisposed so as to expand and contract along the suspension longitudinalline, a distal-side beam longitudinal line that connects center pointsof the proximal and distal ends of the distal-side beam is farther awayfrom the suspension longitudinal center line as it extends toward thedistal side in the suspension longitudinal direction, and aproximal-side beam longitudinal line that connects center points of theproximal and distal ends of the proximal-side beam is farther away fromthe suspension longitudinal center line as it extends in the distal sidein the suspension longitudinal direction.

In any one of the above configurations, the proximal-side beam maypreferably have a width that becomes narrower as it extends from theproximal side to the distal side in the suspension longitudinaldirection.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A to 1C are a top view, a bottom view and a side view of amagnetic head suspension according to a first embodiment of the presentinvention, respectively.

FIG. 2 is a top view of the magnetic head suspension shown in FIG. 1 ina state where paired piezoelectric elements are removed.

FIG. 3 is a cross sectional view taken along line III-III in FIG. 1A.

FIGS. 4A to 4E are top views of magnetic head suspensions according tofirst to fifth examples included in the first embodiment, respectively.

FIGS. 5A to 5E are top views of magnetic head suspensions according tofirst to fifth comparative examples, respectively.

FIG. 6 is a graph showing a result of analysis performed in accordancewith the finite element method with respect to each of the magnetic headsuspensions according to the first to fifth examples and the first tofifth comparative examples that have different inclined angles betweenthe proximal-side beam and the distal-side beam of the connecting beamone another, and shows a width of the connecting beam that is requiredto realize a predetermined micro motion characteristic (8.6 nm/V) ineach of the first to fifth examples and the first to fifth comparativeexamples.

FIG. 7 is a graph showing a result of analysis performed in accordancewith the finite element method for impact resistance with respect toeach of the magnetic head suspensions according to the first to fifthexamples and the first to fifth comparative examples, and shows arelationship between the inclined angle and a stress applied to thepiezoelectric element upon reception of a predetermined impact force ineach of the examples.

FIG. 8 is a graph showing a result of analysis performed in accordancewith the finite element method for resonance frequency with respect toeach of the magnetic head suspensions according to the first to fifthexamples and the first to fifth comparative examples, and FIGS. 8A to 8Eshow relationships of resonance frequencies in the main resonance mode,the first bending mode, the first torsion mode, the second torsion mode,and the third torsion mode with respect to the inclined angle,respectively.

FIG. 9 is a top view of a magnetic head suspension according to a secondembodiment of the present invention.

FIGS. 10A to 10C are a top view, a bottom view, and a side view of amagnetic head suspension according to a third embodiment of the presentinvention, respectively.

FIG. 11 is a top view of the magnetic head suspension shown in FIG. 10in a state where paired piezoelectric elements are removed.

FIG. 12 is an exploded top view of the magnetic head suspension shown inFIG. 10.

FIG. 13 is a cross sectional view taken along line XIII-XIII in FIG.10A.

FIG. 14 is a top view of a magnetic head suspension according to amodification of the third embodiment.

FIGS. 15A to 15C are a top view, a bottom view and a side view of amagnetic head suspension according to a modification of the firstembodiment, respectively.

FIG. 16A is a top view of a magnetic head suspension according to afourth embodiment of the present invention.

FIG. 16B is a bottom view of the magnetic head suspension according tothe fourth embodiment,

FIG. 17 is an enlarged view of XVII portion in FIG. 16A.

FIG. 18 is a top view of a magnetic head suspension according to a fifthembodiment of the present invention.

FIG. 19 is a top view of a magnetic head suspension according to a sixthembodiment of the present invention.

FIG. 20 is a top view of a magnetic head suspension according to amodification of the sixth embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

First Embodiment

Hereinafter, one preferred embodiment of a magnetic head suspensionaccording to the present invention will be described, with reference tothe attached drawings.

FIGS. 1A to 1C are a top view (a plan view as viewed from a sideopposite from a disk surface), a bottom view (a bottom plan view asviewed from a side close to the disk surface) and a side view of amagnetic head suspension 1A according to the present embodiment,respectively. FIG. 1B indicates welding points with using small circles.

As shown in FIGS. 1A to 1C, the magnetic head suspension 1A includes aload bending part 20 that generates a load for pressing a magnetic headslider 50 toward a disk surface, a load beam part 30 that transmits theload to the magnetic head slider 50, a supporting part 10 that supportsthe load beam part 30 via the load bending part 20 and is swung about aswing center directly or indirectly by a main actuator, a flexure part40 that is supported by the load beam part 30 and the supporting part 10while supporting the magnetic head slider 50, and paired right and leftpiezoelectric elements 60 that are attached to the supporting part 10 soas to be symmetrical with each other with respect to a suspensionlongitudinal center line CL and have expansion and contractiondirections different from each other, in order to enable micro motion ofthe magnetic head slider 50 in a seek direction.

The supporting part 10 is a member for supporting the load beam part 30through the load bending part 20 while being directly or indirectlyconnected to the main actuator such as a voice coil motor, and istherefore made to have relatively high rigidity.

In the present embodiment, the supporting part 10 is formed as a baseplate including a boss portion 15 to which a distal end of a carriagearm (not shown) is joined by a swage processing, the carriage arm beingconnected to the main actuator.

The supporting part 10 may be preferably made from, for example, astainless plate having a thickness of 0.1 mm to 0.8 mm.

FIG. 2 is a top view of the magnetic head suspension 1A in a state wherethe paired piezoelectric elements 60 are removed.

As shown in FIGS. 1A to 1C and 2, the supporting part 10 includes aproximal end section 11 that is directly or indirectly connected to themain actuator, a distal end section 12 to which the load bending part 20is connected, an open section 13 that is positioned between the proximalend section 11 and the distal end section 12 in a suspensionlongitudinal direction, and paired right and left connecting beams 14that are positioned on both sides of the open section 13 in a suspensionwidth direction and connect the proximal end section 11 and the distalend section 12.

Detailed configuration of the paired connecting beams 14 will be laterexplained.

As described above, the load beam part 30 is a member for transmittingthe load generated by the load bending part 20 to the magnetic headslider 50, and therefore is required to have a predetermined rigidity.

As shown in FIG. 1A to FIG. 1C and FIG. 2, in the present embodiment,the load beam part 30 has a plate-like main body portion 31 and flangeportions 32 that are formed by being bent in a direction away from thedisk surface at both sides of the main body portion 31 in the suspensionwidth direction, and secures the rigidity by the flange portions 32.

The load beam part 30 may be made from, for example, a stainless platehaving a thickness of 0.02 mm to 0.1 mm.

Specifically, the load beam part 30 is provided, at its distal endsection, with a protrusion 33 that is so-called dimple.

The protrusion 33 is protruded by, for example, about 0.05 mm to 0.1 mm,in a direction toward the disk surface. The protrusion 33 is broughtinto contact with an upper surface (a surface opposite from the disksurface) of a head-mounting region 43 of the flexure part 40, so thatthe load is transmitted to the head-mounting region 43 of the flexurepart 40 through the protrusion 33.

In the present embodiment, the load beam part 30 further integrallyincludes a lift tab 34 that extends from a distal end of the main bodyportion 31 toward a distal end side in the suspension longitudinaldirection. The lift tab 34 is a member that engages with a lamp providedin a magnetic disk device so as to cause the magnetic head suspension 50to be away from the disk surface in z direction (a directionperpendicular to the disk surface) at the time when the magnetic headsuspension 1A is swung by the main actuator so that the magnetic headslider 50 is positioned outward the disk surface in a radial direction.

The load bending part 20 has a proximal end connected to the supportingpart 10 and a distal end connected to the load beam part 30, andgenerates the load for pressing the magnetic head suspension 50 towardthe disk surface in accordance with its elastic deformation.

As shown in FIGS. 1A to 1C and FIG. 2, in the present embodiment, theload bending part 20 includes paired right and left leaf springs 21 thatare disposed so that their plate surfaces face the disk surface.

Preferably, the paired leaf springs 21 are elastically bended in such adirection as to cause the magnetic head suspension 50 to be come closeto the disk surface before the magnetic head suspension 1A is mounted tothe magnetic disk device, and is mounted to the magnetic disk device ina state where the paired leaf springs are elastically bended back so asto generate the pressing load.

The load bending part 20 is made from a stainless steel plate of 0.02 mmto 0.1 mm thick, for example.

In the present embodiment, as shown in FIGS. 1A to 1C and FIG. 2, theload bending part 20 is integrally formed with the load beam part 30.

More specifically, the magnetic head suspension 1A according to thepresent embodiment includes a load beam part component 300 thatintegrally form the load beam part 30 and the load bending part 20. Theload beam part component 300 is welded to the supporting part 10 in astate where an upper surface of the load beam part component 300 that ispoisoned on a side opposite from the disk surface is brought intocontact with a lower surface, which faces the disk surface, of thedistal end section 12 of the supporting part 10.

The flexure part 40 is fixed to the load beam part 30 and the supportingpart 10 while supporting the magnetic head slider 50.

Specifically, the flexure part 40 includes, as shown in FIG. 1B, a bodyregion 41 that is fixed to a surface of the load beam part 30 that facesthe disk surface by welding or the like, paired supporting pieces 42that extends from the body region 41 toward the distal end side, and thehead-mounting region 43 that is supported by the supporting pieces 42.

The head-mounting region 43 supports the magnetic head slider 50 at alower surface that faces the disk surface.

As described above, the protrusion 33 is brought into contact with theupper surface of the head-mounting region 43, so that the head-mountingregion 43 could sway flexibly in a roll direction and in a pitchdirection, with the protrusion 33 functioning as a fulcrum.

The flexure part 40 has rigidity lower than that of the load beam part30, so that the head-mounting region 43 could sway in the roll directionand in the pitch direction.

The flexure part 40 may be preferably made from, for example, astainless plate having a thickness of 0.01 mm to 0.025 mm.

In the present embodiment, the flexure part 40 is provided integrallywith a wiring that is in the form of a printed circuit and transmits awriting signal and/or a reading signal to/from the magnetic head slider50.

That is, the flexure part 40 has a flexure base plate 400 integrallyincluding the body region 41, the supporting pieces 42 and thehead-mounting region 43, and a flexure wring structure 410 laminated onthe flexure base plate 400.

Although the flexure wiring structure 410 is not shown in the figures,it may include an insulating layer laminated on a lower surface of theflexure base plate 400 that faces the disk surface, a conductor layerlaminated on a lower surface of the insulating layer that faces the disksurface, and a cover layer enclosing the conductor layer.

In the present embodiment, as shown in FIG. 1B, the flexure base plate400 is fixed by welding to the main body portion 31 of the load beampart 30, and the distal end section 12 and the proximal end section 11of the supporting part 10.

Each of the piezoelectric elements 60 has a main body made of PZT (leadzirconate titanate) and paired electrode layers disposed on both ends ofthe main body in the thickness direction thereof.

The main body is 0.05 mm to 0.3 mm thick, for example, and the electrodelayers are each made of Ag or Au so as to have a thickness from 0.05 μmto several μm.

As shown in FIG. 1A, each of the paired piezoelectric elements 60 has aproximal end connected to the proximal end section 11 and a distal endconnected to the distal end section 12 in a state of being at leastpartially overlapped with the open section 13 in a plan view as viewedalong a direction perpendicular to the disk surface. Further, the pairedpiezoelectric elements 60 are arranged in such a manner as that one ofthem expands and the other one of them contracts in accordance withapplication of a voltage so that the piezoelectric elements 60 functionas a sub actuator for causing the magnetic head slider 50 to performmicro motion in the seek direction.

FIG. 3 is a cross sectional view taken along line in FIG. 1A.

In the present embodiment, as shown in FIGS. 1A, 1B and 2, the pairedpiezoelectric elements 60 are wholly disposed within the open section 13in a plan view as viewed along the direction perpendicular to the disksurface.

More specifically, the distal ends and the proximal ends of the pairedpiezoelectric elements 60 are fixed to the distal end section 12 and theproximal end section 11, respectively, in a state where the pairedpiezoelectric elements 60 are disposed in the open section 13 such thatend surfaces on the distal end sides and end surfaces on the proximalend sides of the paired piezoelectric elements 60 are opposed at leastpartially to a proximal end surface of the distal end section 12 and adistal end surface of the proximal end section 11, respectively.

According to the configuration, the expansion and contraction motion ofthe paired piezoelectric elements 60 can be transmitted as much aspossible as displacement of the magnetic head slider 50 in the seekdirection.

Moreover, according to the above configuration, the paired piezoelectricelements 60 can be overlapped partially or entirely with the supportingpart 10 in the thickness direction. Therefore, it is possible to reduceas much as possible the thickness of the entire magnetic head suspension1A inclusive of the paired piezoelectric elements 60.

In the present embodiment, the paired piezoelectric elements 60 have theend surfaces on the distal end side that are fixed to the proximal endsurfaces of the distal end section 12 by a fixing member 70 such as aninsulative adhesive agent and the end surfaces on the proximal end sidethat are fixed to the distal end surface of the proximal end section 11by the fixing member 70 such as the insulative adhesive agent in a statewhere the paired piezoelectric elements 60 are wholly arranged in theopen section 13 in a plan view.

That is, the expansion and contraction motion of the pairedpiezoelectric elements 60 is transmitted to the distal end section 12and the proximal end section 11 via the fixing members 70.

As shown in FIGS. 1A to 1C, in the present embodiment, the pairedpiezoelectric elements 60 are disposed such that longitudinal directions(in other words, the expansion and contraction directions) thereof arealigned along the suspension longitudinal direction. However, thepresent invention is not limited to such a configuration.

More specifically, the longitudinal directions of the pairedpiezoelectric elements 60 may be inclined with respect to the suspensionlongitudinal direction as long as the paired piezoelectric elements 60are disposed symmetrically with each other with respect to thesuspension longitudinal center line CL and each of the longitudinaldirections of the paired piezoelectric elements 60 has an element alongthe suspension longitudinal direction.

Application of a voltage to the paired piezoelectric elements 60 can bemade with use of the flexure wiring structure 410, for example.

In the present embodiment, in a state where the upper one (not facingthe disk surface) of the electrode layer of each of the pairedpiezoelectric elements 60 is electrically connected to the supportingpart 10 via a conductive member 72 (see FIG. 1A) such as a conductiveadhesive agent so as to have a ground potential, a voltage is applied tothe lower one (facing the disk surface) of the electrode layers of eachof the paired piezoelectric elements 60 with use of the flexure wiringstructure 410.

Preferably, as shown in FIGS. 1B and 2, the flexure part 40 is arrangedso as to be partially overlapped with the paired piezoelectric elements60 in a plan view as viewed along the direction perpendicular to thedisk surface. The configuration makes it possible to easily applyvoltage to lower electrodes of the paired piezoelectric elements 60using the flexure wiring structure 410.

In the present embodiment, as shown in FIGS. 1B and 3, the conductorlayer of the flexure wiring structure are electrically connected to thelower electrodes of the paired piezoelectric elements 60 by wirebonding.

FIG. 1B also shows an opening 76 formed at the cover layer for exposingthe conductor layer.

The configuration of the paired connecting beams 14 is now explained.

The paired connecting beams 14 are symmetrical to each other withrespect to the suspension longitudinal center line CL.

As shown in FIGS. 1A, 1B and 2, each of the paired connecting beams 14includes a proximal-side beam 141 that linearly extends from a proximalend connected to the proximal end section 11 to a distal end, and adistal-side beam 142 that linearly extends from a proximal end connectedto the proximal-side beam 141 to a distal end connected to the distalend section 12.

As shown in FIG. 1A, the longitudinal direction of the distal-side beam142 is inclined with respect to the longitudinal direction of theproximal-side beam 141 in a plan view such that a connection point CPbetween the proximal-side beam 141 and the distal-side beam 142 (a crosspoint of the longitudinal center line of the proximal-side beam 141 andthe longitudinal center line of the distal-side beam 142) is locatedcloser to the suspension longitudinal center line CL relative to avirtual line IL connecting the proximal end of the proximal-side beam141 and the distal end of the distal-side beam 142 (a virtual lineconnecting the width center point of the proximal end of theproximal-side beam 141 and the width center point of the distal end ofthe distal-side beam 142).

In other words, each of the connecting beams 14 is bent at theconnection point CP between the proximal-side beam 141 and thedistal-side beam 142 such that the connection point CP is located closerto the suspension longitudinal center line relative to the virtual lineIL.

The magnetic head suspension 1A thus configured is capable ofexcellently maintaining the micro motion characteristic of the magnetichead slider 50 in the seek direction by the paired piezoelectricelements 60, as well as is capable of reducing the stress applied to thepiezoelectric elements 60 upon reception of an impact force and raisingthe resonance frequency of the magnetic head suspension 1A.

In the present embodiment, the distal end section 12, the pairedconnecting beams 14 and the proximal end section 11 are integrallyformed by a single member.

Specifically, a supporting part component 100 forming the supportingpart 10 integrally includes a region forming the distal end section 12,a region forming the paired connecting beams 14, and a region forming aproximal end section 11.

The supporting part component 100 may be made from, for example, aplate-like base plate by pressing work.

Described below is a result of analysis on the magnetic head suspension1A for verification of the advantage thereof in accordance with thefinite element method.

FIGS. 4A to 4E and 5A to 5E are top views of magnetic head suspensionsused in this analysis.

FIGS. 4A to 4E show magnetic head suspensions 1 a to 1 e according tofirst to fifth examples in which the longitudinal direction of thedistal-side beam 142 is inclined with respect to the longitudinaldirection of the proximal-side beam 141 in a plan view such that theconnection point CP between the proximal-side beam 141 and thedistal-side beam 142 is located closer to the suspension longitudinalcenter line CL relative to the virtual line IL.

On the other hand, FIG. 5A shows a magnetic head suspension 9 aaccording to a first comparative example in which the longitudinaldirection of the distal-side beam 142 is located coaxially with thelongitudinal direction of the proximal-side beam 141 in a plan view, andFIGS. 5B to 5E show magnetic head suspensions 9 b to 9 e according tosecond to fifth comparative examples in which the longitudinal directionof the distal-side beam 142 is inclined with respect to the longitudinaldirection of the proximal-side beam 141 in a plan view such that theconnection point CP between the proximal-side beam 141 and thedistal-side beam 142 is located farther away from the suspensionlongitudinal center line CL relative to the virtual line IL.

In the magnetic head suspensions 1 a to 1 e according to the first tofifth examples, inclination angles Δα of the longitudinal direction ofthe distal-side beam 142 with respect to the longitudinal direction ofthe proximal-side beam 141 are set to −84.5°, −68.4°, −50.1°, −25.8°,and −5.4°, respectively.

On the other hand, in the magnetic head suspensions 9 a to 9 e accordingto the first to fifth comparative examples, the inclination angles Δαare set to 0°, +21.8°, +41.7°, +63.7°, and +88.0°, respectively.

With regard to indications of the inclination angles Δα, in a case wherethe inclination angle Δα has a − (minus) value, the longitudinaldirection of the distal-side beam 142 is inclined with respect to thelongitudinal direction of the proximal-side beam 141 such that theconnection point CP between the proximal-side beam 141 and thedistal-side beam 142 is located closer to the suspension longitudinalcenter line CL relative to the virtual line IL. On the other hand, in acase where the inclination angle Δα has a + (plus) value, thelongitudinal direction of the distal-side beam 142 is inclined withrespect to the longitudinal direction of the proximal-side beam 141 suchthat the connection point CP between the proximal-side beam 141 and thedistal-side beam 142 is located farther away from the suspensionlongitudinal center line CL relative to the virtual line IL.

Further, in this analysis, the position of the connection point CP inthe suspension longitudinal direction was determined such that, when Ldenotes the distance in the suspension longitudinal direction from theproximal end of the proximal-side beam 141 to the distal end of thedistal-side beam 142, the distance in the suspension longitudinaldirection from the connection point CP to the proximal end of theproximal-side beam 141 is expressed as ¼×L.

In this analysis, the thicknesses of the load beam part 30, thepiezoelectric element 60, the supporting part 10, the flexure board 400,and the flexure wiring structure 410 were set to 0.025 mm, 0.12 mm, 0.15mm, 0.018 mm, and 0.018 mm, respectively.

Firstly obtained was a necessary width of the connecting beam 14 in eachof the magnetic head suspensions 1 a to 1 e according to the first tofifth examples and the magnetic head suspensions 9 a to 9 e according,to the first to fifth comparative examples in order to equalize themicro motion characteristics by the paired piezoelectric elements 60 inall of these magnetic head suspensions.

More specifically, in each of the magnetic head suspensions 1 a to 1 eaccording to the first to fifth examples and the magnetic headsuspensions 9 a to 9 e according to the first to fifth comparativeexamples, there was obtained the width of each of the paired connectingbeams 14 required to set a displacement characteristic of the magnetichead slider 50 in the seek direction in response to the voltage appliedto the paired piezoelectric elements 60 to 8.6 nm/V.

FIG. 6 shows a result of the analysis.

The width 0.30 mm of the connecting beam 14 indicated by a dashed linein FIG. 6 is the minimum value required to stably form the supportingpart 10 inclusive of the paired connecting beams 14 by pressing work.

More specifically, the width of a beam part needs to be at least twicethe thickness of a plate in order to stably form a member that has ashape including the beam part by pressing work.

As described above, the paired connecting beams 14 are provided at thesupporting part 10. In this analysis, the thickness of the supportingpart 10 inclusive of the paired connecting beams 14 is set to 0.15 mm.

Accordingly, in order to stably form, by pressing work, the supportingpart 10 inclusive of the paired connecting beams 14 under the conditionfor this analysis, each of the paired connecting beams 14 is required tohave the width of at least 0.30 mm.

As apparent from FIG. 6, in the magnetic head suspension 9 a accordingto the first comparative example in which the inclination angle Δα isset to zero (that is, the connecting beam 14 has a linear shape in aplan view), the connecting beam 14 is required to have the minimum widthin order to have the above displacement characteristic. To the contrary,in a case where the value of the inclination angle Δα is increased fromzero into any one of − and + directions, the width of the connectingbeam 14 can be increased while realizing the displacementcharacteristic.

More specifically, in comparison to the configuration in which each ofthe paired connecting beams 14 is formed into the linear shape, theconfiguration in which each of the paired connecting beams 14 is bent atthe connection point CP can have the increased width of each of theconnecting beams 14 while realizing the same micro motioncharacteristic.

Therefore, the configuration in which each of the paired connectingbeams 14 is bent at the connection point CP is recognized as havingimproved pressing performance while having the same micro motioncharacteristic in comparison to the configuration in which each of thepaired connecting beams 14 is formed into the linear shape.

Also, as apparent from FIG. 6, the inclination angle Δα needs to be setto at least 62° in order to set the width of each of the pairedconnecting beams 14 to at least 0.30 mm in the configuration in whichthe longitudinal direction of the distal-side beam 142 is inclined withrespect to the longitudinal direction of the proximal-side beam 141 in aplan view such that the connection point CP is located farther away fromthe suspension longitudinal center line CL relative to the virtual lineIL (namely, the configuration with the inclination angle Δα>0).

To the contrary, in the configuration in which the longitudinaldirection of the distal-side beam 142 is inclined with respect to thelongitudinal direction of the proximal-side beam 141 in a plan view suchthat the connection point CP is located closer to the suspensionlongitudinal center line CL relative to the virtual line IL (namely, theconfiguration with the inclination angle Δα<0), the width of each of thepaired connecting beams 14 can be set to at least 0.30 mm by setting theinclination angle Δα to at most −42°.

That is, the configuration, in which the longitudinal direction of thedistal-side beam 142 is inclined with respect to the longitudinaldirection of the proximal-side beam 141 in a plan view such that theconnection point CP is located closer to the suspension longitudinalcenter line CL relative to the virtual line IL, realizes a desired micromotion characteristic with a smaller inclination angle of thedistal-side beam 142 with respect to the proximal-side beam 141, incomparison to the configuration in which the longitudinal direction ofthe distal-side beam 142 is inclined with respect to the longitudinaldirection of the proximal-side beam 141 in a plan view such that theconnection point CP is located farther away from the suspensionlongitudinal center line CL relative to the virtual line IL.

According to the above, the magnetic head suspension 1A according to thepresent embodiment is recognized as being capable of improving the micromotion characteristic in comparison to a magnetic head suspension inwhich the longitudinal direction of the distal-side beam 142 is inclinedwith respect to the longitudinal direction of the proximal-side beam 141in a plan view such that the connection point CP is located farther awayfrom the suspension longitudinal center line CL relative to the virtualline IL.

Moreover, the configuration, in which the longitudinal direction of thedistal-side beam 142 is inclined with respect to the longitudinaldirection of the proximal-side beam 141 in a plan view such that theconnection point CP is located closer to the suspension longitudinalcenter line CL relative to the virtual line IL, realizes reduction insize in the suspension width direction in comparison to theconfiguration in which the longitudinal direction of the distal-sidebeam 142 is inclined with respect to the longitudinal direction of theproximal-side beam 141 in a plan view such that the connection point CPis located farther away from the suspension longitudinal center line CLrelative to the virtual line IL.

Subsequently described is a result of analysis on impact resistance ofeach of the magnetic head suspensions 1 a to 1 e according to the firstto fifth examples and the magnetic head suspensions 9 a to 9 e accordingto the first to fifth comparative examples.

In this analysis, regarding each of the magnetic head suspensions 1 a to1 e according to the first to fifth examples and the magnetic headsuspensions 9 a to 9 e according to the first to fifth comparativeexamples, in a state where the boss portion 15 is restrained and themagnetic head slider 50 is also restrained so as not to be displaced ina z direction perpendicular to a disk surface, applied to theserestrained regions was a shock wave (sine half wave) having a pulsewidth of 1.0 msec and a peak value of 1000 G in a direction toward thedisk surface, and obtained was the maximum stress caused to the pairedpiezoelectric elements 60.

FIG. 7 shows the result of this analysis.

As apparent from FIG. 7, the maximum stress is applied to the pairedpiezoelectric elements 60 in a case of the inclination angle Δα=0 (inthe case where each of the paired connecting beams 14 has the linearshape in a plan view), and the stress applied to the pairedpiezoelectric elements 60 is reduced as the inclination angle Δα isincreased gradually into any one of the + and − directions.

Accordingly, the configuration in which each of the paired connectingbeams 14 is bent at the connection point CP is recognized as improvingthe impact resistance in comparison to the configuration in which eachof the paired connecting beams 14 is formed into the linear shape.

Also, as apparent from FIG. 7, the case where the inclination angle Δαis increased into the − direction could realize reduction of the stressapplied to the paired piezoelectric elements 60 larger than the casewhere the inclination angle Δα is increased into the + direction.

From this fact, the magnetic head suspension 1A according to the presentembodiment is recognized as improving the impact resistance incomparison to a magnetic head suspension in which the longitudinaldirection of the distal-side beam 142 is inclined with respect to thelongitudinal direction of the proximal-side beam 141 in a plan view suchthat the connection point CP is located farther away from the suspensionlongitudinal center line CL relative to the virtual line IL.

Lastly described is a result of analysis on the resonance frequencies ofthe magnetic head suspensions 1 a to 1 e according to the first to fifthexamples and the magnetic head suspensions 9 a to 9 e according to thefirst to fifth comparative examples.

In this analysis, obtained in accordance with the eigenvalue analysiswere the resonance frequencies in the main resonance mode, the firstbending mode, the first torsion mode, the second torsion mode, and thethird torsion mode of each of the magnetic head suspensions 1 a to 1 eaccording to the first to fifth examples and the magnetic headsuspensions 9 a to 9 e according to the first to fifth comparativeexamples.

FIGS. 8A to 8E respectively show the result of this analysis.

The main resonance mode is a vibration mode of the magnetic headsuspension in the seek direction. The first bending mode is a vibrationmode of bending motion of the magnetic head suspension in the zdirection (perpendicular to the disk surface). The first torsion mode isa vibration mode of torsion motion of the load bending part about thesuspension longitudinal center line. The second torsion mode is avibration mode of torsion motion of the supporting part about thesuspension longitudinal center line. The third torsion mode is avibration mode of torsion motion of the load beam part about thesuspension longitudinal center line.

As seen in FIG. 8B, the configuration in which each of the pairedconnecting beams 14 is bent at the connection point CP is capable ofraising the resonance frequency in the first torsion mode in comparisonto the configuration in which each of the paired connecting beams 14 isformed into the linear shape.

Further, as apparent from FIGS. 8A to 8E, the configuration, in whichthe longitudinal direction of the distal-side beam 142 is inclined withrespect to the longitudinal direction of the proximal-side beam 141 in aplan view such that the connection point CP is located closer to thesuspension longitudinal center line CL relative to the virtual line ILrealizes improved resonance frequency characteristics in the firstbending mode and the second torsion mode while having similar resonancefrequency characteristics in the main resonance mode, the first torsionmode, and the third torsion mode, in comparison to the configuration inwhich the longitudinal direction of the distal-side beam 142 is inclinedwith respect to the longitudinal direction of the proximal-side beam 141in a plan view such that the connection point CP is located farther awayfrom the suspension longitudinal center line CL relative to the virtualline IL.

From this fact, the magnetic head suspension 1A according to the presentembodiment is recognized as improving the resonance frequencycharacteristic in comparison to a magnetic head suspension in which thelongitudinal direction of the distal-side beam 142 is inclined withrespect to the longitudinal direction of the proximal-side beam 141 in aplan view such that the connection point CP is located farther away fromthe suspension longitudinal center line CL relative to the virtual lineIL.

Moreover, as shown in FIGS. 1A, 1B, and 2, in the magnetic headsuspension 1A according to the present embodiment, the proximal-sidebeam 141 is inclined so as to be brought gradually closer to thesuspension longitudinal center line CL from the proximal end toward thedistal end thereof.

This configuration makes it possible to increase the distance in thesuspension width direction between the proximal ends of theproximal-side beams 141 of the paired connecting beams 14, therebyachieving stable support of the distal end section 12 by the pairedconnecting beams 14.

Second Embodiment

Hereinafter, another embodiment of the magnetic head suspensionaccording to the present invention will be described, with reference tothe attached drawings.

FIG. 9 is a top view (a plan view as viewed from a side opposite fromthe disk surface) of a magnetic head suspension 1B according to thepresent embodiment.

In the figure, the members same as those in the first embodiment aredenoted by the same reference numerals to omit the detailed descriptionthereof.

As shown in FIG. 9, the magnetic head suspension 1B according to thepresent embodiment is different from the magnetic head suspension 1Aaccording to the first embodiment only in that the shape of thedistal-side beam 142 is changed.

More specifically, in the first embodiment, the width of the distal-sidebeam 142 is substantially constant in the entire region in thelongitudinal direction.

To the contrary, in the present embodiment, the width of the distal-sidebeam 142 is increased gradually toward the distal end from the proximalend that is connected to the corresponding proximal-side beam 141.

With regard to each of the magnetic head suspension 1B according to thepresent embodiment and the magnetic head suspension 1A according to thefirst embodiment, the micro motion characteristic of the magnetic headslider 50 in the seek direction as well as the resonance frequency inthe main resonance mode were analyzed in accordance with the finiteelement method. The micro motion characteristic for the former was 8.3nm/V and that for the latter was 8.5 nm/V. The resonance frequency inthe main resonance mode for the former was 26.5 kHz and that for thelatter was 26.3 kHz.

According to these results, the magnetic head suspension 1B according tothe present embodiment is recognized as raising the resonance frequencyof the magnetic head slider 50 in the main resonance mode in comparisonto the magnetic head suspension 1A according to the first embodiment.

Third Embodiment

Hereinafter, still another embodiment of the magnetic head suspensionaccording to the present invention will be described, with reference tothe attached drawings.

FIGS. 10A to 10C are a top view (a plan view as viewed from a sideopposite from the disk surface), a bottom view (a bottom plan view asviewed from a side close to the disk surface) and a side view of amagnetic head suspension 1C according to the present embodiment,respectively. FIG. 10B indicates welding points with using smallcircles.

The magnetic head suspension 1C according to the present embodiment ismainly different from the magnetic head suspension 1A according to thefirst embodiment in that there are further provided a distal-end-sidesupport plate 80 and a proximal-end-side support plate 90 on which thedistal and proximal sides of the paired piezoelectric elements 60 aremounted, respectively.

FIG. 11 is a top view of the magnetic head suspension 1C in a statewhere the paired piezoelectric elements 60 are removed.

FIG. 12 is an exploded top view of the magnetic head suspension 1C.

FIG. 13 is a cross sectional view taken along line XIII-XIII in FIG.10A.

As shown in FIGS. 9 to 13, the distal-end-side support plate 80 isconnected to the lower surface (the surface facing the disk surface) ofthe supporting part 10, and is configured so that the lower surfaces,which face the disk surface, of the distal sides of the pairedpiezoelectric elements 60 are mounted on an upper surface of thedistal-end-side support plate 80.

Provision of the distal-end-side support plate 80 improves efficiency inattaching the paired piezoelectric elements 60 to the distal end section12.

More specifically, an insulative adhesive agent 70 is applied to theupper surface (not facing the disk surface) of the distal-end-sidesupport plate 80 and the paired piezoelectric elements 60 are thenplaced on the upper surface of the distal-end-side support plate 80, sothat the insulative adhesive agent 70 is spread between the end surfaceson the distal ends of the paired piezoelectric elements 60 and the endsurface on the proximal end of the distal end section 12 of thesupporting part 10.

As shown in FIGS. 11 and 13, in the case of the present embodiment wherethe distal-end-side support plate 80 is provided separately from thesupporting part 10, the distal-end-side support plate 80 is preferablyconnected to the supporting part 10 so as to form a gap 81 between thedistal edge of the distal-end-side support plate 80 and the proximaledge of the distal end section 12 of the supporting part 10 in a planview as viewed along a direction perpendicular to the disk surface.

Such a configuration exerts the following effect.

Specifically, it may be possible to configure the distal-end-sidesupport plate 80 so as to cross over the proximal edge of the distal endsection 12 in a plan view, that is, to provide the distal-end-sidesupport plate 80 in such a manner as that its distal end overlaps withthe distal end section 12 in a plan view. However, when the insulativeadhesive agent is applied onto the upper surface of the distal-end-sidesupport plate 80 and the paired piezoelectric elements 60 are thenplaced on the upper surface of the distal-end-side support plate 80 soas to fix the paired piezoelectric elements 60 onto the distal endsection 12, this configuration may cause the insulative adhesive agent70 to enter between the distal-end-side support plate 80 and the distalend section 12, which are ideally in intimate contact with each other.Both of the distal-end-side support plate 80 and the distal end section12 are provided as rigid members such as SUS and are ideally in intimatecontact with each other. Accordingly, if the insulative adhesive agent70 enters between these two members, the filler included in theinsulative adhesive agent 70 may get out of the location between thesetwo members in accordance with the expansion and contraction motion ofthe paired piezoelectric elements 60.

On the other hand, such a defect can be effectively prevented in theconfiguration where the distal-end-side support plate 80 is disposed soas to provide the gap 81 between the distal edge of the distal-end-sidesupport plate 80 and the proximal edge of the distal end section 12 in aplan view.

In the present embodiment, the distal-end-side support plate 80 isintegrally formed with a load beam part component 300C that integrallyforms the load beam part 30 and the load bending part 20.

Specifically, as shown in FIG. 12, the load beam part component 300Cincludes a load beam part forming region 330 that forms the load beampart 30, paired load bending part forming region 320 that forms thepaired leaf springs 21 functioning as the load bending part 20, pairedsupporting part fixed region 310 that extend toward the proximal endside of the suspension from the paired load bending part forming region320 and is fixed to the supporting part 10 in a state of being broughtinto contact therewith, a connecting region 350 that connects the pairedsupporting part fixed region 310 in a state of overlapping with thedistal end section 12 in a plan view, and distal-end-side support plateforming region 380 that is positioned on the distal end side of theconnecting region 350 and connects the paired supporting part fixedregion 30 so as to form the distal-end-side support plate 80.

In the configuration including the distal-end-side support plate 80 asin the present embodiment, the inner surface of each of the distal-sidebeams 142 that is directed inward in the suspension width direction ispreferably formed to be brought closest to the outer surface of thecorresponding piezoelectric element 60 that is directed outward in thesuspension width direction at a position of the piezoelectric element 60that is away by a predetermined distance from its distal end toward itsproximal end.

This configuration can effectively prevent the insulative adhesive agent70 from flowing out toward the proximal end in the suspensionlongitudinal direction from between the inner surface of each of thedistal-side beams 142 and the outer surface of the correspondingpiezoelectric element 60, when the insulative adhesive agent 70 isapplied onto the upper surface of the distal-end-side support plate 80and the paired piezoelectric elements 60 are then placed on the uppersurface of the distal-end-side support plate 80 so as to fix the pairedpiezoelectric elements 60 onto the distal end section 12. Thereforesuppressed are variation in the micro motion characteristic of themagnetic head slider 50 in the seek direction as well as variation inthe resonance frequency characteristic of the magnetic head suspension1C.

As shown in FIGS. 10A, 11, and 12, in the present embodiment, each ofthe distal-side beams 142 is provided on the inner surface with aninward projection 142 a that projects inward in the suspension widthdirection at a position away by a predetermined distance from the distalend toward the proximal end of the corresponding piezoelectric element60. Provision of the inward projection 142 a prevents the insulativeadhesive agent 70 from flowing out toward the proximal end in thesuspension longitudinal direction.

As shown in FIGS. 10A to 10C, and 11 to 13, the proximal-end-sidesupport plate 90 is connected to the lower surface (the surface facingthe disk surface) of the supporting part 10, and is configured so thatthe lower surfaces, which face the disk surface, of the proximal sidesof the paired piezoelectric elements 60 are mounted on an upper surfaceof the proximal-end-side support plate 90.

Provision of the proximal-end-side support plate 90 improves efficiencyin attaching the paired piezoelectric elements 60 to the proximal endsection 11.

More specifically, an insulative adhesive agent 70 is applied to theupper surface (not facing the disk surface) of the proximal-end-sidesupport plate 90 and the paired piezoelectric elements 60 are thenplaced on the upper surface of the proximal-end-side support plate 90,so that the insulative adhesive agent 70 is spread between the endsurfaces on the proximal ends of the paired piezoelectric elements 60and the end surface on the distal end of the proximal end section 11 ofthe supporting part 10.

As shown in FIGS. 11 and 13, in the case of the present embodiment wherethe proximal-end-side support plate 90 is provided separately from thesupporting part 10, the proximal-end-side support plate 90 is preferablyconnected to the supporting part 10 so as to form a gap 91 between theproximal edge of the proximal-end-side support plate 90 and the distaledge of the proximal end section 11 of the supporting part 10 in a planview as viewed along a direction perpendicular to the disk surface.

Such a configuration exerts the following effect.

Specifically, it may be possible to configure the proximal-end-sidesupport plate 90 so as to cross over the distal edge of the proximal endsection 11 in a plan view, that is, to provide the proximal-end-sidesupport plate 90 in such a manner as that its proximal end overlaps withthe proximal end section 11 in a plan view. However, when the insulativeadhesive agent is applied onto the upper surface of theproximal-end-side support plate 90 and the paired piezoelectric elements60 are then placed on the upper surface of the proximal-end-side supportplate 90 so as to fix the paired piezoelectric elements 60 onto theproximal end section 11, this configuration may cause the insulativeadhesive agent 70 to enter between the proximal-end-side support plate90 and the proximal end section 11, which are ideally in intimatecontact with each other. Both of the proximal-end-side support plate 90and the proximal end section 11 are provided as rigid members such asSUS and are ideally in intimate contact with each other. Accordingly, ifthe insulative adhesive agent 70 enters between these two members, thefiller included in the insulative adhesive agent 70 may get out of thelocation between these two members in accordance with the expansion andcontraction motion of the paired piezoelectric elements 60.

On the other hand, such a defect can be effectively prevented in theconfiguration where the proximal-end-side support plate 90 is disposedso as to provide the gap 91 between the proximal edge of theproximal-end-side support plate 90 and the distal edge of the proximalend section 11 in a plan view.

In the present embodiment, the proximal-end-side support plate isintegrally formed with a supporting part component 100C that forms thesupporting part 10.

More specifically, as shown in FIG. 12, the supporting part component100C includes first and second plate-like members 110, 120 that arecontacted and fixed to each other.

The first plate-like member 110 integrally includes a region 111corresponding to the proximal end section 11, a region 114 correspondingto the paired connecting beams 14, and a region 112 corresponding to thedistal end section 112.

The second plate-like member 120 integrally includes a region 121corresponding to the proximal end section 11, and a region 129corresponding to the proximal-end-side support plate 90.

The first and second plate-like members 110, 120 are fixed to each otherby welding in a state where the respective regions 111, 121corresponding to the proximal end section 11 are overlapped with eachother.

In the present embodiment, as shown in FIG. 12, the first plate-likemember 110 is provided with the boss portion 15, and the secondplate-like member 120 is formed with an opening 16 having a diameterlarger than that of a boss hole of the boss portion.

Furthermore, as shown in FIGS. 10A, 11, and 12, in the presentembodiment, the distal end section 12 is provided on the proximal edgethereof with a suspension width central portion 12 a that has a concaveshape open toward the proximal end in the suspension longitudinaldirection in a plan view.

More specifically, the suspension width central portion 12 a provided onthe proximal edge of the distal end section 12 has the concave shape ina plan view so as to be located on the most distal end in the suspensionlongitudinal direction at its center that is crossed with the suspensionlongitudinal center line CL as well as to be brought closer to theproximal end in the suspension longitudinal direction as extendingoutward both in the suspension width direction from the center.

This configuration suppresses the stress from being concentrated ontothe suspension width central portion 12 a of the distal end section 12upon the expansion and contraction motion of the paired piezoelectricelements 60, thereby preventing the insulative adhesive agent 70 frombeing separated, detached, or the like.

Similarly, as shown in FIGS. 10A, 11 and 12, the proximal end section 11is provided on the distal edge thereof with a suspension width centralportion 11 a that has a concave shape open toward the distal end in thesuspension longitudinal direction in a plan view.

More specifically, the suspension width central portion 11 a provided onthe distal edge of the proximal end section 11 has the concave shape ina plan view so as to be located on the most proximal end in thesuspension longitudinal direction at its center that is crossed with thesuspension longitudinal center line CL as well as to be brought closerto the distal end in the suspension longitudinal direction as extendingoutward both in the suspension width direction from the center.

This configuration suppresses the stress from being concentrated ontothe suspension width central portion 11 a of the proximal end section 11upon the expansion and contraction motion of the paired piezoelectricelements 60, thereby preventing the insulative adhesive agent 70 frombeing separated, detached, or the like.

Of course, the formation of the suspension width central portion 12 a ofthe proximal edge of the distal end section 12 and/or the suspensionwidth central portion 11 a of the distal edge of the proximal endsection 11 into the concave shape in a plan view could be also appliedto the magnetic head suspensions 1A, 1B according to the first andsecond embodiments as well as a magnetic head suspension according to amodified embodiment that is described later.

Although the supporting part 10 is in the form of the base plate in eachof the embodiments, it is of course that the present invention is notlimited to the configuration. That is, an arm with a proximal endconnected to the swing center of the main actuator could be adopted asthe supporting part 10.

FIG. 14 is a top view of a magnetic head suspension 1C′ according to amodified embodiment of the present invention in which the supportingpart 10 is changed to the arm in comparison with the magnetic headsuspension 1C according to the third embodiment.

Further, although, in each of the embodiments, the paired piezoelectricelements 60 are disposed within the open section 13, the presentinvention is not limited to the configuration.

More specifically, each of the paired piezoelectric elements 60 can bedisposed so as to have the distal end placed on the upper surface of thedistal end section 12 and the proximal end placed on the upper surfaceof the proximal end section 11 while crossing over the open section 13in the suspension longitudinal direction.

FIGS. 15A to 15C are a top view, a bottom view, and a side view,respectively, of a magnetic head suspension 1A′ according to amodification of the present invention, which is obtained by modifyingthe magnetic head suspension 1A according to the first embodiment insuch a manner as described above.

In the magnetic head suspension 1A′ shown in FIGS. 15A to 15C, althoughthe thickness in the z direction is increased, the paired piezoelectricelements 60 can be fixed to the supporting part 10 more easily.

Fourth Embodiment

Hereinafter, still another embodiment of the magnetic head suspensionaccording to the present invention will be described, with reference tothe attached drawings.

FIGS. 16A and 16B are a top view (a plan view as viewed from a sideopposite from the disk surface) and a bottom view (a bottom plan view asviewed from a side close to the disk surface) of a magnetic headsuspension 1D according to the present embodiment, respectively. FIG.16B indicates welding points with using small circles.

As shown in FIGS. 16A and 16B, the magnetic head suspension 1D includesthe load bending part 20 that generates the load for pressing themagnetic head slider 50 toward the disk surface, the load beam part 30that transmits the load to the magnetic head slider 50, the supportingpart 10 that supports the load beam part 30 via the load bending part 20and is swung about the swing center directly or indirectly by the mainactuator, the flexure part 40 that is supported by the load beam part 30and the supporting part 10 while supporting the magnetic head slider 50,and the paired right and left piezoelectric elements 60 that areattached to the supporting part 10 so as to be symmetrical with eachother with respect to the suspension longitudinal center line CL andhave expansion and contraction directions different from each other, inorder to enable micro motion of the magnetic head slider 50 in the seekdirection.

The supporting part 10 is a member for supporting the load beam part 30through the load bending part 20 while being directly or indirectlyconnected to the main actuator such as the voice coil motor, and istherefore made to have relatively high rigidity.

In the present embodiment, the supporting part 10 is formed as the baseplate including the boss portion 15 to which the distal end of thecarriage arm (not shown) is joined by a swage processing, the carriagearm being connected to the main actuator.

The supporting part 10 may be preferably made from, for example, astainless plate having a thickness of 0.1 mm to 0.8 mm.

It is, of course, possible to adopt, as the supporting part 10, the armthat has a proximal end connected to the swing center of the mainactuator.

The supporting part 10 includes the proximal end section 11 that isdirectly or indirectly connected to the main actuator, the distal endsection 12 to which the load bending part 20 is connected, the opensection 13 that is positioned between the proximal end section 11 andthe distal end section 12 in the suspension longitudinal direction, andpaired right and left connecting beams 14D that are positioned on bothsides of the open section 13 in the suspension width direction andconnect the proximal end section 11 and the distal end section 12.

Detailed configuration of the paired connecting beams 14 will be laterexplained.

As described above, the load beam part 30 is a member for transmittingthe load generated by the load bending part 20 to the magnetic headslider 50, and therefore is required to have a predetermined rigidity.

As shown in FIGS. 16A and 16B, in the present embodiment, the load beampart 30 has the plate-like main body portion 31 and the flange portions32 that are formed by being bent in a direction away from the disksurface at both sides of the main body portion 31 in the suspensionwidth direction, and secures the rigidity by the flange portions 32.

The load beam part 30 may be made from, for example, a stainless platehaving a thickness of 0.02 mm to 0.1 mm.

Specifically, the load beam part 30 is provided, at its distal endsection, with the protrusion 33 that is so-called dimple.

The protrusion 33 is protruded by, for example, about 0.05 mm to 0.1 mm,in a direction toward the disk surface. The protrusion 33 is broughtinto contact with the upper surface (the surface opposite from the disksurface) of the head-mounting region 43 of the flexure part 40, so thatthe load is transmitted to the head-mounting region 43 of the flexurepart 40 through the protrusion 33.

In the present embodiment, the load beam part 30 further integrallyincludes the lift tab 34 that extends from the distal end of the mainbody portion 31 toward the distal end side in the suspensionlongitudinal direction. The lift tab 34 is a member that engages withthe lamp provided in the magnetic disk device so as to cause themagnetic head suspension 50 to be away from the disk surface in zdirection (the direction perpendicular to the disk surface) at the timewhen the magnetic head suspension 1D is swung by the main actuator sothat the magnetic head slider 50 is positioned outward the disk surfacein the radial direction.

The load bending part 20 has the proximal end connected to thesupporting part 10 and the distal end connected to the load beam part30, and generates the load for pressing the magnetic head suspension 50toward the disk surface in accordance with its elastic deformation.

As shown in FIGS. 16A and 16B, in the present embodiment, the loadbending part 20 includes the paired right and left leaf springs 21 thatare disposed so that their plate surfaces face the disk surface.

Preferably, the paired leaf springs 21 are elastically bended in such adirection as to cause the magnetic head suspension 50 to be come closeto the disk surface before the magnetic head suspension 1A is mounted tothe magnetic disk device, and is mounted to the magnetic disk device ina state where the paired leaf springs are elastically bended back so asto generate the pressing load.

The load bending part 20 is made from a stainless steel plate of 0.02 mmto 0.1 mm thick, for example.

In the present embodiment, as shown in FIGS. 16A and 16B, the loadbending part 20 is integrally formed with the load beam part 30.

More specifically, the magnetic head suspension 1D according to thepresent embodiment includes the load beam part component 300 thatintegrally form the load beam part 30 and the load bending part 20. Theload beam part component 300 is welded to the supporting part 10 in astate where the upper surface of the load beam part component 300 thatis poisoned on a side opposite from the disk surface is brought intocontact with the lower surface, which faces the disk surface, of thedistal end section 12 of the supporting part 10.

The flexure part 40 is fixed to the load beam part 30 and the supportingpart 10 while supporting the magnetic head slider 50.

Specifically, the flexure part 40 includes, as shown in FIG. 13B, thebody region 41 that is fixed to the surface of the load beam part 30that faces the disk surface by welding or the like, the pairedsupporting pieces 42 that extends from the body region 41 toward thedistal end side, and the head-mounting region 43 that is supported bythe supporting pieces 42.

The head-mounting region 43 supports the magnetic head slider 50 at thelower surface that faces the disk surface, as shown in FIG. 16B.

As described above, the protrusion 33 is brought into contact with theupper surface of the head-mounting region 43, so that the head-mountingregion 43 could sway flexibly in a roll direction and in a pitchdirection, with the protrusion 33 functioning as a fulcrum.

The flexure part 40 has rigidity lower than that of the load beam part30, so that the head-mounting region 43 could sway in the roll directionand in the pitch direction.

The flexure part 40 may be preferably made from, for example, astainless plate having a thickness of 0.01 mm to 0.025 mm.

In the present embodiment, the flexure part 40 is provided integrallywith the wiring that is in the form of a printed circuit and transmits awriting signal and/or a reading signal to/from the magnetic head slider50.

That is, the flexure part 40 has the flexure base plate 400 integrallyincluding the body region 41, the supporting pieces 42 and thehead-mounting region 43, and the flexure wiring structure 410 that is atleast partially laminated on the flexure base plate 400.

The flexure wring structure 410 may include the insulating layerlaminated on the lower surface of the flexure base plate 400 that facesthe disk surface, the conductor layer laminated on the lower surface ofthe insulating layer that faces the disk surface, and the cover layerenclosing the conductor layer.

In the present embodiment, the flexure base plate 400 is fixed bywelding to the main body portion 31 of the load beam part 30, and thedistal end section 12 and the proximal end section 11 of the supportingpart 10.

Each of the piezoelectric elements 60 has the main body made of PZT(lead zirconate titanate) and the paired electrode layers disposed onboth ends of the main body in the thickness direction thereof.

The main body is 0.05 mm to 0.3 mm thick, for example, and the electrodelayers are each made of Ag or Au so as to have a thickness from 0.05 μmto several μm.

As shown in FIGS. 16A and 16B, each of the paired piezoelectric elements60 has the proximal end connected to the proximal end section 11 and thedistal end connected to the distal end section 12 in a state of being atleast partially overlapped with the open section 13 in a plan view asviewed along the direction perpendicular to the disk surface.

Further, the paired piezoelectric elements 60 are arranged in such amanner as that one of them expands and the other one of them contractsin accordance with application of a voltage so that the piezoelectricelements 60 function as a sub actuator for causing the magnetic headslider 50 to perform micro motion in the seek direction.

In the present embodiment, as shown in FIGS. 16A and 16B, the pairedpiezoelectric elements 60 are wholly disposed within the open section 13in a plan view as viewed along the direction perpendicular to the disksurface.

More specifically, the distal ends and the proximal ends of the pairedpiezoelectric elements 60 are fixed to the distal end section 12 and theproximal end section 11, respectively, in a state where the pairedpiezoelectric elements 60 are disposed in the open section 13 such thatthe end surfaces on the distal end sides and the end surfaces on theproximal end sides of the paired piezoelectric elements 60 are opposedat least partially to the proximal end surface of the distal end section12 and the distal end surface of the proximal end section 11,respectively.

According to the configuration, the expansion and contraction motion ofthe paired piezoelectric elements 60 can be transmitted as much aspossible as displacement of the magnetic head slider 50 in the seekdirection.

Moreover, according to the above configuration, the paired piezoelectricelements CO can be overlapped partially or entirely with the supportingpart 10 in the thickness direction. Therefore, it is possible to reduceas much as possible the thickness of the entire magnetic head suspension1C inclusive of the paired piezoelectric elements 60.

In the present embodiment, the paired piezoelectric elements 60 have theend surfaces on the distal end side that are fixed to the proximal endsurfaces of the distal end section 12 by the fixing member 70 such as aninsulative adhesive agent and the end surfaces on the proximal end sidethat are fixed to the distal end surface of the proximal end section 11by the fixing member 70 such as the insulative adhesive agent in a statewhere the paired piezoelectric elements 60 are wholly arranged in theopen section 13 in a plan view.

That is, the expansion and contraction motion of the pairedpiezoelectric elements 60 is transmitted to the distal end section 12and the proximal end section 11 via the fixing members 70.

As shown in FIGS. 16A and 16B, in the present embodiment, the pairedpiezoelectric elements 60 are disposed such that longitudinal directions(in other words, the expansion and contraction directions) thereof arealigned along the suspension longitudinal direction. However, thepresent invention is not limited to such a configuration.

More specifically, the longitudinal directions of the pairedpiezoelectric elements 60 may be inclined with respect to the suspensionlongitudinal direction as long as the paired piezoelectric elements 60are disposed symmetrically with each other with respect to thesuspension longitudinal center line CL and each of the longitudinaldirections of the paired piezoelectric elements 60 has an element alongthe suspension longitudinal direction.

Application of a voltage to the paired piezoelectric elements 60 can bemade with use of the flexure wiring structure 410, for example.

More specifically, the conductor layer of the flexure wiring structure410 may be configured so as to have a piezoelectric element conductivemember as well as a slider conductive member electrically connected tothe magnetic head slider 50, and the electrode layer on the lower side(the side facing the disk surface) of each of the paired piezoelectricelements 60 may be electrically connected to the piezoelectric elementconductive member.

The electric connection could be made by, for example, wire bonding, orconductive adhesive agent.

The electrode layer on the upper side (the side opposite from the disksurface) of each of the paired piezoelectric elements 60 is electricallyconnected to the supporting part 10 via a conductive member such as aconductive adhesive agent so as to have a ground potential.

The configuration of the paired connecting beams 14D is now explained.

FIG. 17 is an enlarged view of XVII portion in FIG. 16A.

The paired connecting beams 14D are symmetrical to each other withrespect to the suspension longitudinal center line CL, as shown in FIGS.16A and 16B.

In the connecting beam 14D, the virtual line SL connecting the centerpoint of the proximal end 14 a to be connected to the proximal endsection 11 and the center point of the distal end 14 b to be connectedto the distal end section 12 is gradually brought closer to thesuspension longitudinal center line CL as it extends toward the distalend in the suspension longitudinal direction.

More specifically, in the present embodiment, the distal end section 12of the supporting part 10 has a length in the suspension width directionshorter than that of the distal end of the proximal end section 11, sothat the virtual line IL is brought closer to the suspensionlongitudinal center line CL as it extends toward the distal end in thesuspension longitudinal direction.

Such a configuration is capable of reducing the moment of inertia of thesub actuator around the rotational center, thereby raising the resonancefrequency in the main resonance mode.

Furthermore, in this configuration, the weight of the supporting part 10can be reduced on the distal end, so that raised is the resonancefrequency in the bending mode in the z direction perpendicular to thedisk surface. As a result, reduced is the stress applied to thepiezoelectric elements 60 upon reception of an impact force, therebyimproving the impact resistance of the magnetic head suspension 1D.

Furthermore, in the present embodiment, the paired connecting beams 14Dhas a following structure in order to improve the micro motioncharacteristics in the seek direction of the magnetic head slider 50 bythe paired piezoelectric elements 60.

More specifically, as shown in FIGS. 16A, 16B and 17, each of the pairedconnecting beams 14D includes a proximal-side beam 141D that extendsfrom the proximal end 14 a connected to the proximal end section 11toward the distal side in the suspension longitudinal direction, adistal-side beam 142D that extends from the distal end 14 b connected tothe distal end section 12 toward the proximal side in the suspensionlongitudinal direction, and an intermediate beam 143D connecting adistal end of the proximal-side beam 141D and a proximal end of thedistal-side beam 142D.

As shown in FIGS. 16A, 16B, and 17, in each of the connecting beams 14D,the connection point between the proximal-side beam 141D and theintermediate beam 143D configures a first bent portion 14 c and theconnection point between the distal-side beam 142D and the intermediatebeam 143D configures a second bent portion 14 d such that anintermediate beam longitudinal line 143D(L) connecting the center pointof the proximal end and the center point of the distal end of theintermediate beam 143D is across the virtual line IL.

In such a configuration, the bend angles of the bent portions 14 c and14 d, which are provided between the proximal end 14 a and the distalend 14 b of the connecting beam 14D, can be set within a range (such as±60° from 90°) reasonably allowing the elastic deformation of theconnecting beam 14D, without significantly extending the connecting beam14D outward in the suspension width direction. Therefore, prevented asmuch as possible is deterioration in rigidity in the z directionperpendicular to the disk surface, and improved is the micro motioncharacteristic of the magnetic head slider 50 by the piezoelectricelements 60 (namely, the degree of easiness for displacement of themagnetic head slider 50 by the piezoelectric elements 60 in the seekdirection in parallel with the disk surface).

More specifically, the expansion and contraction motion of thepiezoelectric elements 60 in the suspension longitudinal directioncauses elastic deformation of each of the connecting beams 14D so thatthe proximal end 14 a and the distal end 14 b of the connecting beam 14Dare spaced apart from or brought closer to each other in the suspensionlongitudinal direction. Accordingly, the load bending part 20 and theload beam part 30 are swung in the seek direction so that the magnetichead slider 50 is shifted in the seek direction.

Therefore, in order to improve the micro motion characteristic in theseek direction of the magnetic head slider 50 by the piezoelectricelements 60, each of the connecting beams 14D needs to be formed so asto easily enables the elastic deformation of bringing the proximal end14 a and the distal end 14 b of the connecting beam 14D close to eachother in the suspension longitudinal direction as well as the elasticdeformation of separating the proximal end 14 a and the distal end 14 bfrom each other in the suspension longitudinal direction.

In this regard, described first are the preferable ranges of the bendangles of the bent portions 14 c and 14 d that are provided in each ofthe connecting beams 14D.

For example, in a case where the connecting beam 14D is formed into alinear shape in the entire length (that is, the case where theconnecting beam 14D is formed to be aligned along the virtual line IL,which corresponds to the case where the angle α1 or α2 shown in FIG. 17is 180°), it is difficult to elastically deform the connecting beam 14Dso that the proximal end 14 a and the distal end 14 b of the connectingbeam 14D are brought closer to or spaced apart from each other by theexpansion and contraction motion of the corresponding piezoelectricelement 60.

To the contrary, in a case where the bent portion of the connecting beam14D has a too small bend angle (that is, the case where the angle α1 orα2 shown in FIG. 17 is too much approximated to 0°), the connecting beam14D is formed into a shape along the virtual line IL. In this case, itis also difficult to elastically deform the connecting beam 14D so thatthe proximal end 14 a and the distal end 14 b of the connecting beam 14Dare brought closer to or spaced apart from each other by the expansionand contraction motion of the corresponding piezoelectric element 60.

In view of the above, the bent portions provided in the connecting beam14D each have a preferable range of the bend angle (such as ±60° from90°, namely, from 30° to 120′).

Described next is the preferable number of the bent portions that areprovided in each of the connecting beams 14D.

As described above, in the present embodiment, each of the connectingbeams 14D has the bent portion 14 c (hereinafter, referred to as firstbent portion) that is located at the connection point between theproximal-side beam 141D and the intermediate beam 143D as well as thebent portion 14 d (hereinafter, referred to as second bent portion) thatis located at the connection point between the distal-side beam 142D andthe intermediate beam 143D.

As shown in FIG. 17, the first bent portion 14 c is bent at the firstbend angle α1 (α1=approximately 89° in this figure) which falls withinthe preferable range of the bend angle, and the second bent portion 14 dis bent at the second bend angle α2 (α2=approximately 81° in thisfigure) which falls within the preferable range of the bend angle.

Consideration is given to a connecting beam 240 that has only one bentportion bent at the bend angle identical to the first bend angle α1. Asshown in FIG. 17, the connecting beam 240 projects farther outward inthe suspension width direction in comparison to the connecting beam 14Dof the present embodiment, thereby causing deterioration in rigidity inthe z direction perpendicular to the disk surface.

Furthermore, in the case where the connecting beam 14D is formed toproject outward in the suspension width direction, there is caused arisk that the connecting beam 14D is brought into undesired contact witha different component configuring a hard disk drive.

As shown in FIG. 17, a connecting beam 241, which has only one bentportion bent at the bend angle identical to the second bend angle α2, isformed to project farther inward in the suspension width direction incomparison to the connecting beam 14D of the present embodiment.

Accordingly, in order to avoid an undesired contact with thecorresponding piezoelectric element 60, the proximal end section 11 andthe distal end section 12 of the supporting part 10 need to be extendedoutward in the suspension width direction so that the connecting beam241 is located farther outside in the suspension width directionrelative to the state shown in FIG. 17. As a result, deteriorated is therigidity in the z direction perpendicular to the disk surface.

Moreover, in the case where the proximal end section 11 and the distalend section 12 of the supporting part 10 are projected outward in thesuspension width direction, there is caused a risk that the proximal endsection 11 or the distal end section 12 is brought into undesiredcontact with a different component configuring the hard disk drive.

To the contrary, as described above, each of the connecting beams 14D inthe present embodiment is bent at two positions of the first bentportion 14 c and the second bent portion 14 d such that the intermediatebeam longitudinal line 143D(L) is crossed with the virtual line IL.

Therefore, each of the bent portions 14 c and 14 d can be set to have abend angle in the preferable range without significantly extending theconnecting beam 14D outward in the suspension width direction. As aresult, it is possible to improve the micro motion characteristic of themagnetic head slider 50 by the piezoelectric elements 60 whilepreventing as much as possible the deterioration in rigidity in the zdirection perpendicular to the disk surface.

Furthermore, as shown in FIGS. 16A, 16B, and 17, in the presentembodiment, the first bent portion 14 c connecting between theproximal-side beam 141D and the intermediate beam 143D is locatedoutside the virtual line IL in the suspension width direction, and thesecond bent portion 14 d connecting between the distal-side beam 142Dand the intermediate beam 143D is located inside the virtual line IL inthe suspension width direction.

In this configuration, the distal-side beam 142D of the connecting beam14D that is positioned on the distal side can be located as closer aspossible to the suspension longitudinal center line CL, while theintermediate beam longitudinal line 143D(L) being crossed with thevirtual line IL.

Therefore, it is possible to raise the resonance frequency in the mainresonance mode in comparison to a configuration according to amodification in which the first bent portion 14 c is located inside thevirtual line IL in the suspension width direction and the second bentportion 14 d is located outside the virtual line IL in the suspensionwidth direction.

Fifth Embodiment

Hereinafter, still another embodiment of the magnetic head suspensionaccording to the present invention will be described, with reference tothe attached drawings.

FIG. 18 is a top view (a plan view as viewed from a side opposite fromthe disk surface) of a magnetic head suspension 1E according to thepresent embodiment.

In the figure, the members same as those in the above-explainedembodiments are denoted by the same reference numerals to omit thedetailed description thereof.

The magnetic head suspension 1E according to the present embodiment isdifferent from the magnetic head suspension 1D in that the connectingbeams 14D are replaced with connecting beams 14E.

Specifically, in the fourth embodiment, as shown in FIGS. 16A, 16B and17, the proximal-side beam 141D of each of the connecting beams 14D isarranged so that a proximal-side beam longitudinal line 141D(L), whichconnects the center point of the proximal end 14 a and a center point ofa distal end, is substantially parallel to the expansion and contractiondirection of each of the paired piezoelectric elements 60.

That is, in the fourth embodiment, each of the piezoelectric elements 60is arranged so that the expansion and contraction direction is along thesuspension longitudinal direction, and the proximal-side beam 141D isarranged so that proximal-side beam longitudinal line 141D(L) is alongthe suspension longitudinal direction.

To the contrary, in the present embodiment, as shown in FIG. 18, theconnecting beam 14E has a proximal-side beam 141E arranged so that itsproximal-side beam longitudinal line 141E(L), which connects the centerpoint of the proximal end 14 a and a center point of a distal end, isbrought closer to the suspension longitudinal center line CL as itextends in the distal side in the suspension longitudinal direction, andis inclined with respect to the expansion and contraction direction ofeach of the paired piezoelectric elements 60.

More specifically, although each of the paired piezoelectric elements 60is arranged so that its expansion and contraction direction is along thesuspension longitudinal direction as in the fourth embodiment, theproximal-side beam longitudinal line 141E(L) is inclined with respect tothe expansion and contraction direction of the piezoelectric element 60so as to be brought closer to the suspension longitudinal center line CLas it extends toward the distal side in the suspension longitudinaldirection.

Furthermore, in both of the fourth embodiment and the presentembodiment, the distal-side beam 142D is disposed so that a distal-sidebeam longitudinal line 142D(L), which connects a center point of theproximal end and a center point of the distal end 14 b, is farther awayfrom the suspension longitudinal center line CL as it extends toward thedistal side in the suspension longitudinal direction.

That is, in the present embodiment, both of the longitudinal lines141E(L), 142D(L) of the proximal-side beam 141E and the distal-side beam142D are inclined with respect to the expansion and contractiondirection of each of the paired piezoelectric elements 60.

The configuration makes it possible to more easily make an elasticdeformation of the connecting beams 141E by the expansion andcontraction motion of the paired piezoelectric elements 60, therebyimproving the micro motion characteristic of the magnetic head slider 50in the seek direction by the paired piezoelectric elements 60.

Further, since the proximal-side beam 141E is inclined so that theproximal-side beam longitudinal line 141E(L) is brought closer to thesuspension longitudinal center line CL as it extends in the distal sidein the suspension longitudinal direction, the configuration makes itpossible to reduce the moment of inertia of the proximal-side beam 141Earound the suspension longitudinal center line CL larger than the fourthembodiment, thereby raising the resonance frequency of the magnetic headsuspension.

Sixth Embodiment

Hereinafter, still another embodiment of the magnetic head suspensionaccording to the present invention will be described, with reference tothe attached drawings.

FIG. 19 is a top view (a plan view as viewed from a side opposite fromthe disk surface) of a magnetic head suspension 1F according to thepresent embodiment.

In the figure, the members same as those in the above-explainedembodiments are denoted by the same reference numerals to omit thedetailed description thereof.

The magnetic head suspension 1F according to the present embodiment isdifferent from the magnetic head suspensions 1D, 1E in that theconnecting beams 14D, 14E are replaced with connecting beams 14F.

In the present embodiment, each of the connecting beams 14F has aproximal-side beam 141F whose proximal-side beam longitudinal line141F(L) is inclined with respect to the expansion and contractiondirection of each of the paired piezoelectric elements 60 so as to befarther away from the suspension longitudinal center line CL as itextends in the distal side in the suspension longitudinal direction.

The configuration makes it also possible to more easily make an elasticdeformation of the connecting beams 141F by the expansion andcontraction motion of the paired piezoelectric elements 60, therebyimproving the micro motion characteristic of the magnetic head slider 50in the seek direction by the paired piezoelectric elements 60.

Further, in the present embodiment, each of the connecting beams 14F isconfigured so that both the distal-side beam longitudinal line 142F(L)and the proximal-side beam longitudinal line 141F(L) are farther awayfrom the suspension longitudinal center line CL as it extends toward thedistal side in the suspension longitudinal direction.

That is, the distal-side beam longitudinal line 142D(L) and theproximal-side beam longitudinal line 141F(L) are inclined in the sameside with the suspension longitudinal direction being as a reference.

The configuration makes it possible to make an elastic deformation ofthe connecting beams 14F without difficulty in either case of expansionor contraction of the piezoelectric element 60.

Preferably, as shown in FIG. 20, a proximal-side beam 141F′ whose widthbecomes narrower as it extends from the proximal side to the distal sidein the suspension longitudinal direction may be adopted.

A magnetic head suspension 1F′ according to the modified example makesit possible to raise resonance frequencies in the bending mode, thetorsion mode and the main resonance mode.

It is of course possible that the proximal-side beam 141F′ whose widthbecomes narrower as it extends from the proximal side to the distal sidein the suspension longitudinal direction is adopted to the magnetic headsuspensions 1D, 1E according to the fourth and fifth embodiments.

What is claimed is:
 1. A magnetic head suspension comprising a loadbending part that generates a load for pressing a magnetic head slidertoward a disk surface, a load beam part that transmits the load to themagnetic head slider, a supporting part that supports the load beam partvia the load bending part and is swung about a swing center directly orindirectly by a main actuator, a flexure part that is supported by theload beam part and the supporting part while supporting the magnetichead slider, and paired right and left piezoelectric elements that areattached to the supporting part so as to be symmetrical with each otherwith respect to a suspension longitudinal center line and have expansionand contraction directions different from each other, in order to enablemicro motion of the magnetic head slider in a seek direction, whereinthe supporting part includes a proximal end section that is directly orindirectly connected to the main actuator, a distal end section to whichthe load bending part is connected, an open section that is positionedbetween the proximal end section and the distal end section in asuspension longitudinal direction, and paired right and left connectingbeams that are positioned on both sides of the open section in asuspension width direction and connect the proximal end section and thedistal end section, wherein each of the paired piezoelectric elementshas proximal and distal ends that are connected to the proximal endsection and the distal end section, respectively, while being at leastpartially overlapped with the open section in a plan view as viewedalong a direction perpendicular to the disk surface, and wherein asuspension width central portion of a proximal edge of the distal endsection is formed into a concave shape in a plan view so as to belocated on the most distal side in the suspension longitudinal directionat its center that is crossed with the suspension longitudinal centerline as well as to be brought closer to the proximal side in thesuspension longitudinal direction as extending outward in both sides inthe suspension width direction from the center.
 2. A magnetic headsuspension according to claim 1, wherein the distal and proximal ends ofeach of the paired piezoelectric elements are fixed to the distal endsection and the proximal end section, respectively, in a state where thepiezoelectric element is disposed in the open section such that an endsurface on the distal end side and an end surface on the proximal endside of the piezoelectric element are opposed at least partially to aproximal end surface of the distal end section and a distal end surfaceof the proximal end section, respectively, and wherein the concave shapein the plan view at the distal end section is positioned on the distalside in the suspension longitudinal direction farther than the endsurfaces on the distal end sides of the paired piezoelectric elements.3. A magnetic head suspension according to claim 2, further comprising adistal-end-side support plate, which is connected to a lower surface ofthe supporting part that faces the disk surface and on which lowersurfaces, on the distal sides, of the paired piezoelectric elements thatface the disk surface are mounted, wherein the distal-end-side supportplate is connected to the lower surface of the supporting part so as toform a gap between a distal edge of the distal-end-side support plateand a proximal edge of the distal end section in a plan view as viewedalong a direction perpendicular to the disk surface.
 4. A magnetic headsuspension according to claim 3, wherein the load beam part, the loadbending part and the distal-end-side support plate are integrally formedby a single member.
 5. A magnetic head suspension according to claim 1,wherein a suspension width central portion of a distal edge of theproximal end section is formed into a concave shape in a plan view so asto be located on the most proximal side in the suspension longitudinaldirection at its center that is crossed with the suspension longitudinalcenter line as well as to be brought closer to the distal side in thesuspension longitudinal direction as extending outward in both sides inthe suspension width direction from the center.
 6. A magnetic headsuspension according to claim 5, wherein the distal and proximal ends ofeach of the paired piezoelectric elements are fixed to the distal endsection and the proximal end section, respectively, in a state where thepiezoelectric element is disposed in the open section such that an endsurface on the distal end side and an end surface on the proximal endside of the piezoelectric element are opposed at least partially to aproximal end surface of the distal end section and a distal end surfaceof the proximal end section, respectively, and wherein the concave shapein the plan view at the proximal end section is positioned on theproximal side in the suspension longitudinal direction farther than theend surfaces on the proximal end sides of the paired piezoelectricelements.
 7. A magnetic head suspension according to claim 1, whereinthe distal and proximal ends of each of the paired piezoelectricelements are mounted on upper surfaces of distal end section and theproximal end section, respectively, in a state where the piezoelectricelements cross over the open section in the suspension longitudinaldirection.
 8. A magnetic head suspension according to claim 1, whereinthe supporting part is a base plate including a boss portion to which adistal end of a carriage arm is joined by a swage processing, thecarriage arm being connected to the main actuator.
 9. A magnetic headsuspension according to claim 1, wherein the supporting part is an armthat is connected to the main actuator.
 10. A magnetic head suspensioncomprising a load bending part that generates a load for pressing amagnetic head slider toward a disk surface, a load beam part thattransmits the load to the magnetic head slider, a supporting part thatsupports the load beam part via the load bending part and is swung abouta swing center directly or indirectly by a main actuator, a flexure partthat is supported by the load beam part and the supporting part whilesupporting the magnetic head slider, and paired right and leftpiezoelectric elements that are attached to the supporting part so as tobe symmetrical with each other with respect to a suspension longitudinalcenter line and have expansion and contraction directions different fromeach other, in order to enable micro motion of the magnetic head sliderin a seek direction, wherein the supporting part includes a proximal endsection that is directly or indirectly connected to the main actuator, adistal end section to which the load bending part is connected, an opensection that is positioned between the proximal end section and thedistal end section in a suspension longitudinal direction, and pairedright and left connecting beams that are positioned on both sides of theopen section in a suspension width direction and connect the proximalend section and the distal end section, wherein each of the pairedpiezoelectric elements has proximal and distal ends that are connectedto the proximal end section and the distal end section, respectively,while being at least partially overlapped with the open section in aplan view as viewed along a direction perpendicular to the disk surface,and wherein a suspension width central portion of a distal edge of theproximal end section is formed into a concave shape in a plan view so asto be located on the most proximal side in the suspension longitudinaldirection at its center that is crossed with the suspension longitudinalcenter line as well as to be brought closer to the distal side in thesuspension longitudinal direction as extending outward in both sides inthe suspension width direction from the center.
 11. A magnetic headsuspension according to claim 10, wherein the distal and proximal endsof each of the paired piezoelectric elements are fixed to the distal endsection and the proximal end section, respectively, in a state where thepiezoelectric element is disposed in the open section such that an endsurface on the distal end side and an end surface on the proximal endside of the piezoelectric element are opposed at least partially to aproximal end surface of the distal end section and a distal end surfaceof the proximal end section, respectively, and wherein the concave shapein the plan view at the proximal end section is positioned on theproximal side in the suspension longitudinal direction farther than theend surfaces on the proximal end sides of the paired piezoelectricelements.
 12. A magnetic head suspension according to claim 11, furthercomprising a proximal-end-side support plate, which is connected to alower surface of the supporting part that faces the disk surface and onwhich lower surfaces, on the proximal sides, of the paired piezoelectricelements that face the disk surface are mounted, wherein theproximal-end-side support plate is connected to the lower surface of thesupporting part so as to form a gap between a proximal edge of theproximal-end-side support plate and a distal edge of the proximal endsection in a plan view as viewed along a direction perpendicular to thedisk surface.
 13. A magnetic head suspension according to claim 12,wherein the supporting part includes first and second plate-like membersthat are overlapped with and fixed to each other, wherein the firstplate-like member integrally includes a region corresponding to theproximal end section, a region corresponding to the paired connectingbeams, and a region corresponding to the distal end section, and whereinthe second plate-like member integrally includes a region correspondingto the proximal end section, and a region corresponding to theproximal-end-side support plate.
 14. A magnetic head suspensionaccording to claim 10, wherein each of the paired connecting beamsincludes a proximal-side beam that linearly extends from a proximal endconnected to the proximal end section to a distal end, and a distal-sidebeam that linearly extends from a proximal end connected to theproximal-side beam to a distal end connected to the distal end section,and wherein the distal-side beam is inclined with respect to theproximal-side beam in a plan view such that a connection point betweenthe proximal-side beam and the distal-side beam is located closer to thesuspension longitudinal center line relative to a virtual lineconnecting the proximal end of the proximal-side beam and the distal endof the distal-side beam.
 15. A magnetic head suspension according toclaim 14, wherein the proximal-side beam is inclined so as to be broughtcloser to the suspension longitudinal center line as extending from theproximal end to the distal end.
 16. A magnetic head suspension accordingto claim 14, wherein the distal-side beam has a width that is graduallyincreased as extending from the proximal end to the distal end.